An investor is an entity that commits money to a venture with an expectation of generating a return. The type of commitment made can be in many forms, such as a guarantee to pay creditors, a loan, an equity investment, tangible assets, or even the contribution of labor. An investor typically makes a commitment in exchange for either a fixed return (such as dividends or interest) or the prospect of being able to sell its investment to a third party at a later date for a higher price than the amount of the original investment.

An investor can be an individual or a corporate entity. For example, a corporation could contribute funds to a joint venture, in which case the corporation is an investor in the joint venture.